ATP, NAD, $Mg^{2+}$ 및 무기인(無機燐)의 보충하(補充下)에 사람과 가토용혈액(家兎溶血液)의 해당률(解糖率)(유산산출량(乳酸産出量))을 측정(測定)하고，이에 미치는 미혈구(未血球) 막(膜)의 영향(影響)을 관찰(觀察)하였다. 가토용혈액(家兎溶血液)의 해당률(解糖率)은 사람 것과는 달리 적혈구막분획(赤血球膜分劃)에 의하여 억제(抑制)되었으나，이때 적혈구막(赤血球膜)을 미리 $50^{circ}$이상(以上)에서 열처리(熱處理)하거나 혹은 반응액(反應液)에 nicotinamide를 가(加)하면 해당률(解糖率)은 억제(抑制)되지 아니하였다. 적혈구막(赤血球膜)의 NAD glycohydrolase, adenosinetriphosphatase 및 acetylcholinesterase 활성(活性)을 사람과 가토적혈구(家兎赤血球)에서 비교(比較)한 바 양자간(兩者間)에 가장 현저(顯著)한 활성차(活性差)를 나타낸 것은 NAD glycohydrolase로서 가토(家兎) 것이 사람 것보다 90 배(倍)나 더 높았다. 적혈구막분획(赤血球膜分劃)에 의한 무기인(無機燐)의 in vitro 섭취(攝取)는 사람과 가토간(家兎間)에 큰 차(差)가 없었다. 이상(以上)의 가험성적(家驗成績)을 통하여 가토용혈액(家兎溶血液)에 있어서 막분획(膜分劃)에 의한 해체율저하(解體率低下)는 적혈구막(赤血球膜)의 NAD glycohydrolase 작용(作用)에 기인(起因)함을 알 수 있었다. NAD 농도(濃度)가 0.06mM 이하(以下)가 되면 해당률(解糖率)은 현저(顯著)히 감소(減少)되며 또 NAD 분해산물(分解産物)의 하나인 adenosine diphosphate ribose도 해당률(解糖率)을 저하(低下)시킴을 밝혔다.
The effects of erythrocyte membrane on the glycolytic capactity of hemolysate from human and rabbits were studied in a system fortified with ATP, $Mg^{2+}$ and inorganic phosphate. The glycolytic capacitty was assessed by the measurement of lactate production. In marked contrast to the human hemolysate, the rabbit hemolysate showed a strikingly reduced rate of glycolysis when the erythrocyte membrane fraction way; added. The reduction in glycolysis was, however, prevented by the preliminary heat-treatment above $50^{circ}$ of the membrane fraction or by the addition of nicotinamide in the reaction mixture. The measurement of the activities of membrane-bound enzymes (NAD glycohydrolase, adenosinetriphosphatase, and acetylcholinesterase) revealed that NAD glycohydrolase showed the most marked species-difference, the activity of rabbit erythrocytes being 90-fold greater than the human one. On the other hand, there could not be found any species-difference in the in vitro uptake of inorganic phosphate by the membrane fractions. It was also found that when the concentration of NAD was less than 0.06 mM, the hemolysate glycolysis was markedly lowered, and that adenosines diphosphate ribose, a product from NAD splitting, exhibited an inhibitory effect on the glycolysis. These results indicate that the reduced glycolysis in rabbit hemolysate observed by the addition of erythrocyte membrane can be ascribed to the membrane-bound NAD glycohydrolase.
